wp_register_widget_control()在小工具管理界面上创建控制选项，以便用户对设置进行修改

The options contains the height, width, and id_base keys. The height
option is never used. The width option is the width of the fully expanded
control form, but try hard to use the default width. The id_base is for
multi-widgets (widgets which allow multiple instances such as the text
widget), an id_base must be provided. The widget id will end up looking like{$id_base}-{$unique_number}.